Does caesarean section increase the risk of childhood cancer?

We will discuss “Delivery by caesarean section and childhood cancer: a nationwide follow-up study in three countries” by Momen and co-workers from 28 May 2014. The paper will be made free-to-view for four weeks from 19 May 2014. 

Start date: 28 May 2014 (the discussion will open for 7 days)

First hosted discussion session(s) starts at: Noon EST/ 5pm UK time (GMT+1) 

Host: @BlueJCHost

Platforms: Twitter

The Blue Journal Club is an international journal club on women’s health research based on Twitter (as @BlueJCHost). We start our conversation on the last Wednesday of each month and use the hashtag #BlueJC for our tweets. Simply add this hashtag (“#BlueJC”) to each tweet and we will capture it. Each #BlueJC opens for 7 days with an advertised start time.

All BJOG #BlueJC papers also have complementary slide sets suitable for face-to-face journal clubs with your local colleagues. You can access the slide set of this paper here (data S1).

The discussion points are attached below (quoted from the published manuscript)

Scenario A paediatric oncologist at your institute observes that a substantial proportion of her cancer patients were born by caesarean section. She asks if you know of any data suggesting an association between caesarean birth and childhood cancers.

 Description of research

Participants Children born in Denmark (1973–2007), Sweden (1973–2008) and Finland (1987–2007) with a recorded mode of birth
Intervention Birth by caesarean section (elective, unplanned or unknown)
Comparison Children not born by caesarean section
Outcomes All childhood cancers. Childhood cancer, stratified by subtype
Study design Retrospective cohort

Discussion points

  • Do the hypotheses with regard to caesarean section and childhood cancer favour an association or causation? How does one prove causation?
  • What are the advantages of a retrospective cohort design? What other study type might have been used?
  • What potential confounding factors were not addressed in the adjusted models?
  • How does confounding by indication relate to the association between caesarean section and testicular cancer?
  • If a significant association between caesarean section and testicular cancer had been found, would that affect your clinical practice?
  • Based on this work, how would you answer the paediatric oncologist in the scenario above? (Data S1)

For those who want to understand hashtags, this may be a useful guide. For an introduction to #BlueJC, please refer to BJOG 2013;120:657–60. Follow @BlueJCHostthis blog and our Facebook page to receive news about #BlueJC.